diversity of fishes 2/biology 2/exam 4... · actinopterygii osteichthyes teleostei sarcopterygii...
TRANSCRIPT
Phylum: Chordata
Deuterostomes
radial and indeterminate cleavage
Enterocoelous
anus from blastopore
Bilateral Symmetry
Both invertebrates and vertebrates
Contain four anatomical features
Phylum: Chordata
Notochord
Dorsal, Hollow
Nerve Cord
Pharyngeal Slits
Muscular,
Postanal Tail
Subphylum: Urochordata
Tunicates
Sessile
Only contains Pharynx with slits as an adult
Subphylum: Cephalochordata
Lancelates
Contains all four
chordate
characters as an
adult
Closest relative
to vertebrates
(Amphioxus)
Paedogenesis
SubPhylum: Vertebrata
Backbones
Contains all four chordate characters as an adult with modification
Neural Crest bones and
cartilage of the skull
Vertebrate Adaptations
Living Endoskeleton better for larger animals
Pharynx and Efficient Respiration increased metabolic rate
Advanced Nervous System developed system for distance
reception
Paired Limbs increased movement
Chordate
Evolution
Vertebrae
Jaws and two sets of
paired appendages
Teeth
Lungs
Legs
Amniotic Egg
Hair, feathers
Introduction to Fishes“Fish”: poikilothermic, aquatic chordate with appendages developed as fins (when present),
whose chief respiratory organ are gills and whose body is usually covered in scales
Paraphyletic group because of tetrapods
All fishes…
have distinct head region (eyes, mouth, etc.) and brain protected by braincase
Most fishes…
live in water
breathe with gills rather than lungs
are unable to regulate their body temperature
are covered in scales
have paired limbs in the form of fins
Diversity of Fishes
More fish species than birds, reptiles and mammals combined
27,900 species described
58% live in salt water, 41% in freshwater, and 1% move between salt and freshwater
Life span
Pygmy goby < 60 days Shape
Rockfish >200 years
Size
Minnow ≈ 0.3 in
Whale shark > 65ft
Actinopterygii
Osteichthyes
Teleostei
Sarcopterygii
Gnathostomata
Holostei
Protacanthopterygii
Synapomorphies: 1) Slime production 2) Ammocoetes larvae. 3) Jaws. 4) Cartilaginous
skeleton 5) Ossified endoskeleton. 6) Lobed fins. 7) Rayed-fins. 8) Mobile pre-maxilla (jaw
protrusion), uroneural bone. 9) Leptocephalus larve. 10) Bony tongue. 11) Inner ear to gas
bladder connection. 12) Weberian apparatus. 13) Adipose fin. 14) Spiny rays on first dorsal,
ascending process, pectoral and pelvic girdle connection, pharyngeal dentition. 15) Fused
jaw, bony plates. 16) Finlets. 17) Flattened body. 18) Jaw teeth. 19) Lateral pectoral fins,
abdominal pelvic fins. 20) Bony plate/spines on cheek.
Osteriophysi
Acanthopterygii
Stomiatii
12
3
4
5
6
7
8
9
10
11
12
13
15
14
16
17
18 19
20
Modes of Reproduction Oviparous: lay eggs that hatch outside of the mother’s
body Some sharks and most fish
Ovoviviparous: mother retains fertilized eggs within the oviduct, but does not provide nourishment to the eggs Few sharks
Viviparous: young develop within mother’s uterus and receive nourishment via the placenta, uterus or by eating other eggs, before being born (live birth) Some sharks and fish
Respiration in Fishes
Osmoregulation in Fish Osmoconformers: isotonic (same solute concentration) to surrounding water
Most marine invertebrates, hagfish, elasmobranchs
Osmoregulators: actively regulate body osmolarity (solute concentration)
Most fish
Endothermy in Fish
Some tuna, billfish, and sharks
Countercurrent heat exchange
Maintains elevated swim muscle temperature
Thermogenic organs
Evolutionary advantages:
Expansion of thermal niche
Stabilize temperature of internal tissues
Increased metabolic rates
Increased neural processing and vision
Evolution of Vertebrate Excretory System
Pronephros: simple nephron which
collects filtrate from coelom through
ciliated nephrostomes before filtration
in the pronephric duct
Found in jawless fish (Agnatha) and
larval amphibians
Glomerulus (Glomus): cluster of
capillaries
Evolution of Vertebrate Excretory System
Mesonephros: collection of
mesonephric tubules which form
capsules around glomeruli where
filtration occurs
Found in fish, adult amphibians,
and embryonic mammals
Develops into reproductive
organs in male mammals
Ureteric bud develops into
metaneophros (kidney in birds,
reptiles and mammals)
Glomerulus
Filtrate
Afferent
arteriole
Efferent
arteriole
Bowman’s
capsule
Superclass Agnatha, Order Myixiniformes
Hagfish
Jawless (Superclass Agnatha)
Reduced vertebrae with cartilaginous
braincase
Marine scavengers
Produce slime
Lack scales and paired appendages
Reduced brain, eyes, ears, and nasal
opening
Tie themselves in a knot to release
slime or provide leverage when feeding
Barbels
Superclass Agnatha, Order PetromyzontiformesLampreys
Jawless (Superclass Agnatha)
Rudimentary vertebrae and cartilaginous skeleton
Marine and freshwater
Anadromous: migrates to fresh water to spawn
Ammocoetes larvae: filter feeders, buried in sediment
Most are parasitic
Lack scales and paired appendages
Evolution of Jaws Jaws likely developed from gill arches used in filter feeding
Lead to the diversification of food types (carnivory and herbivory)
Allowed for active defense from predators
De-emphasis on armored plates
Development of paired appendages
Class Chondrichthyes (kon-DRIK-thee-EEZ) First appeared in mid-Devonian
Cartilaginous skeleton
Placoid scales
Teeth derived from placoid scales are not fused with jaw
Replaceable (every few day)
Large, buoyant livers
Lack gas bladder or lungs
Spiral valve intestine
Highly developed sensory organs
Ampullae de Lorenzini
Internal fertilization
Claspers
Ampullae de Lorenzini
Spiral valve
Placoid scales
Class Chondrichthyes
Subclass Elasmobranchii
Sharks (8 orders, ~360 species)
Most are large (> 1m)
Most are active marine predators
Skates, Rays, Electric rays, Sawfish (4 orders, ~550 species)
Flattened bodies
Bottom dwelling predators
Subclass Holocephali
Chimaera (rat fish) (1 extant order, ~50 species)
Feed on benthic invertebrates in deep ocean
Class Chondrichthyes, Subclass Elasmobranchii
Sharks
Charcharhiniformes (210 species)
Tiger, Hammerhead, Blacktip
Two dorsal fins, an anal fin, and
5 gill openings
Nictitating membrane
Lamniformes (16 species)
Mako, Great white, Thresher, Basking
Elevated body temp
Two dorsal fins, an anal fin, and
5 gill openings
Nictitating membrane
Nictitating membrane
Dorsal fins
Anal finGill openings
Class Chondrichthyes, Subclass Elasmobranchii
Order Rajiformes (Skates)
Thorns on back
No stinging spine
Two lobes on pelvic fin
Lay eggs (Oviparous)
Order Myliobatiformes (Rays)
No thorns on back
Stinging spine
One lobe on pelvic fin
Live birth (viviparous)
Two lobesSingle lobe
Thorns
Class Chondrichthyes, Subclass HolocephaliChimaera (ratfish)
Oviparous
Upper jaw attached to braincase
Teeth modified as crushing plates
Diet of benthic invertebrates
Poisonous spine before first dorsal fin
Move by flapping pectoral fins
Lack scales
Osteichthyes (AH-stee-IK-thee-eez) Bony fishes
Ossified (bony) endoskeleton
Pair of lungs or swim bladder
Bony fin rays
Ganoid, ctenoid, or cycloid scales (no placoid)
Operculum: bony gill cover
Divided into two classesClass Sarcopterygii (sar-KOP-tuh-RIJ-ee-eye)
Lobe-finned fishes
Pectoral and pelvic fins made of rod-shaped bones surrounded by muscle
Class Actinopterygii (ACK-tih-NOP-tuh-RIJ-ee-eye)
Ray-finned fishes
Elongated, flexible fin rays
Single dorsal fin
Lobed fin
Rayed fin
Basic Anatomy of a Bony Fish
Lateral line: sensory organ used to
detect vibrations and movements
Swim bladder (gas bladder): internal
air filled organ that aids in buoyancy
Lateral Line
Class Sarcopterygii, Order Coelocantiformes
Coelocanths
Three lobed caudal fin
Fleshy operculum
Jointed skull
Viviparous
Rostral organ: electroreceptive organ
located in the front of the braincase
Believed to have gone extinct 65mya
Re-discovered in 1938
Populations near Indonesia and South Africa
Class Sarcopterygii, Subclass DipnoiLungfish
All freshwater fish
Lungs
Breathe air
Homologous to tetrapods
Slender fins
Single, long tapered caudal fin
Omnivorous diet
Can survive dry conditions by estivating in mucus-lined burrow for up to 4 years!
Largest genome among vertebrates
Estivation
Class Actinopterygii, Order AcipenseriformesSturgeons and Paddlefishes
Primitive characteristics Mostly cartilaginous skeleton
Heterocercal tail
Spiral valve intestine
Lack of vertebral centra
Marine, freshwater and anadromous
Caviar
Barbels
4 in Sturgeons
2 in Paddlefish
Lack scales
Class Actinopterygii, Infraclass Holostei Brackish waters
Highly vascularized swim bladder Can breathe air
Veracious predators Stalk prey
Order Amiiformes (Bowfins) Single extant species
Gular plate
Swims via dorsal fin
Order Lepisosteiformes (Gars) Ganoid scales
Heterocercal tail
Gular plate
Ganoid scales
96% of all living fishes (38 orders and 426 families)
Occupy nearly all freshwater and marine habitats
Most diverse group of all vertebrates
Significant variation in body plans, foraging and reproductive behaviors
Only herbivorous fishes
Diverged in the Mesozoic Era
Uroneural bones
Homocercal caudal fin
Mobile pre-maxilla bone
Jaw protrusion
Class Actinopterygii, Infraclass Teleostei
Class Actinopterygii, Superorder Elopomorpha
Leptocephalus larvae: flat, ribbon-shaped, transparent larvae
Large size
Long life
Order Anguilliformes True eels
Elongated fish with dorsal and anal fins fused with caudal fin
Order Albuliformes Bone fish
Hard, bony scales
Order Elopiformes Tarpon
Bony tongues
Teeth on the tongue bite against bones
on the roof of the mouth
Mostly tropical
Arapaima and Arowana
Some of the largest fresh water fishes
Elephant fish
Produced and detects weak electrical fields
Large brain
Class Actinopterygii, Superorder Osteoglossomorpha
Class Actinopterygii, Superorder Clupeimorpha
Anchovies and Sardines
Inner ear to gas bladder connection
Physostomes
Quickly adjust pressure in gas bladder
Improves hearing of low frequency sounds
Most are marine, open water schooling
species
Filter feeders
Important commercial fish
Food source for many predators
including marine mammals, seabirds, and
large predatory fish like tuna and marlin
Class Actinopterygii, Superorder Osteriophysi
Minnows, Catfish, Knifefish, Piranha
Dominant freshwater fish species
Weberian apparatus: set of bones that
connect the inner ear to the gas bladder
Improved hearing
Response to alarm signals of conspecifics
Weberian
ossicles
Brain
Semicircular
canals
Vertebrae
Ribs
Swim
bladder
Cypriniformes: Minnows, Carp, Shiners
2nd largest order of fish
Early pharyngeal dentition
Invasive species in many freshwater habitats
Characiformes: Piranha, Tetras
Mostly tropical
Mouth teeth and replacement dentition
Adipose fin
Siluriformes: Catfish
Barbels
No scales
Class Actinopterygii, Superorder Osteriophysi
Order Salmoniformes: Salmon and Trout Freshwater, anadromous
Adipose fin
Ecologically and commercially important species
Reduced populations Alteration to river systems (Dams)
Fish ladder
Overfishing
Order Escoiformes: Pike Fins far back on body
Freshwater
Voracious predators Cannibalistic
Class Actinopterygii, Superorder Protacanthopterygi
Adipose fin
Order Osmeriformes: Smelt
Small, silvery, elongate fishes
Single soft rayed dorsal fin
Freshwater, marine, anadromous
Delta smelt and Candlefish
Order Stomiiformes: Dragonfish, hatchetfish
Deep sea
Bioluminescence
Photophores
Class Actinopterygii, Superorder Stomiatii
Class Actinopterygii, Superorder: Scopelomorpha
Lanternfish
Deep sea fishes
Laterally compressed, with large eyes
Bioluminescence
Photophores
Majority of deep sea biomass (65%)
Diel vertical migration
From ~ 10,000ft deep to ~ 30ft deep
Important food source for marine predators
High lipid content
Photophores
Class: Actinopterygii, Superorder: Acanthopterygii
Spiny-rayed fishes
Spiny rays on first dorsal fin, pelvic and anal fin
Two dorsal fins (1st spiny, 2nd soft)
Ascending process of premaxilla
Improved jaw protrusion
Pharyngeal dentition
Specialized depending on food type
Spiny fin rays
Soft fin rays
Ascending process
Class: Actinopterygii, Superorder: Acanthopterygii
Pelvic girdle attached to
pectoral girdle
Pelvic fin with anterior
spine and 5 soft rays
Ctenoid scales
Spine
Pectoral girdle
Pelvic girdle
Superorder: Acanthopterygii, Order Gadiformes
Cod, Haddock, Pollock
Benthic marine
Nocturnally active
Barbels
Three dorsal fins, two anal fins
Commercially important
Fish and chips!
Populations declines due to overfishing
Superorder: Acanthopterygii, Order Syngathiformes
Pipefish, Seahorses, Seadragons
Fused jaws form long snout
Pivot feeding (Supa fast!)
Plates of body armor
Lack pelvic fins
Prehensile tail
Males carry eggs in pouch or on tail
Superorder: Acanthopterygii, Order Scombriformes
Tuna, Mackerel, Bonito
Large, fast marine predators
Most are schooling
Open ocean (pelagic)
Two dorsal fins and strong caudal fin
Finlets behind dorsal and anal fins
Regional endothermy
Non-protrusable jaw
Commercially important food
Populations declining
Overfishing
Finlets
Superorder: Acanthopterygii, Order Perciformes
Wrasses, Bass, Cichlids, and
Perch
Largest vertebrate order
Contains ~ 40% of all fish species
Abdominal pelvic fins and lateral
pectoral fins
Male Female
Lateral Pectoral fin
Abdominal pelvic fin
Superorder: Acanthopterygii, Order Scorpeniformes
Rockfish and Sculpin
Bony ridge/spines on cheek
Most have spines on head
Round pectoral and caudal fins
Carnivorous
Live near bottom
Long livedSpines on cheek
Superorder: Acanthopterygii, Order Plueronectiformes
Flatfishes (flounders, soles, halibut)
Bilaterally symmetric larvae
metamorphose into flat formed adults
Left-eyed or right-eyed
Benthic carnivores
Camouflaged
Commercially
important
Superorder: Acanthopterygii, Order Tetradontiformes
Triggerfish, Pufferfish, Mola Mola
Teeth in the outer jaws
Derived from jaw bone (not true teeth)
Four in some pufferfish
Mostly tropical reefs
Often eat animals inaccessible
to other fishes
Sponges, sea jellies, sea urchins, corals
Mola mola’s can have >300,000,000 eggs!
Superorder: Acanthopterygii, Order Antheriniformes
Silversides (Topsmelt, Grunion)
Two separate dorsal fins are
common
Single spine on anal fin
Weak or absent lateral line
Surface-dwelling fish
Beach spawning in grunion
Two dorsal fins
Actinopterygii
Osteichthyes
Teleostei
Sarcopterygii
Gnathostomata
Holostei
Protacanthopterygii
Synapomorphies: 1) Slime production 2) Ammocoetes larvae. 3) Jaws. 4) Cartilagenous
skeleton 5) Ossified endoskeleton. 6) Lobed fins. 7) Rayed-fins. 8) Mobile pre-maxilla (jaw
protrusion), uroneural bone. 9) Leptocephalus larve. 10) Bony tongue. 11) Inner ear to gas
bladder connection. 12) Weberian apparatus. 13) Adipose fin. 14) Spiny rays on first dorsal,
ascending process, pectoral and pelvic girdle connection, pharyngeal dentition. 15) Fused
jaw, bony plates. 16) Finlets. 17) Flattened body. 18) Jaw teeth. 19) Lateral pectoral fins,
abdominal pelvic fins. 20) Bony plate/spines on cheek.
Osteriophysi
Acanthopterygii
Stomiatii
12
3
4
5
6
7
8
9
10
11
12
13
15
14
16
17
18 19
20